Current drinking water limits appear to be “several hundredfold too high.”
The Minnesota Department of Health has a “ Health Risk Limit” of 300 nanograms/liter for C8 (PFOA) one of a family of perfluorinated chemicals (PFCs) make by 3M Company that has caused widespread contamination of drinking water in Minnesota and elsewhere. This limit was adopted in 2008 or 2009 and replaced a limit of 500 nanograms/liter adopted in 2007. That replaced an earlier limit of 1000 n/L. It means in practice that if C8 levels in drinking water are below this level, the water is considered safe to drink by federal and Minnesota officials.
On January 15, 2009, the USEPA set a “provisional health advisory level” of 400 nanograms/liter in drinking water, so this level is probably used by most states.
The State of New Jersey has adopted a level of 40 nanograms/liter.
These limits are based primarily on liver damage.
A recently published, peer-reviewed paper to be published in the journal Environmental Health (publication date April 19, 2013, 14 pages) breaks new ground, concluding that “current limits appear to be several hundred fold too high. Current drinking water limits therefore need to be reconsidered.” A few excepts follow:
“The benchmark dose results obtained are in accordance with recent data on toxicity in experimental models. When the results are converted to approximate exposure limits for drinking water, current limits appear to be several hundred fold too high. Current drinking water limits therefore need to be reconsidered.”
“PFC toxicity in animal models at first suggested the liver as a main target organ, but so far chronic toxicity data only on the rat have been published [1,12,17,18]. However, recent evidence suggests that toxicology outcomes used in derivation of exposure limits may not represent the most sensitive endpoints.”
“Likewise, immunotoxicity of PFCs has been demonstrated …”
“Given the concern about immunotoxicity as a possible critical effect [19] and the possibility of developmental toxicity [23], studies in child populations have recently focused on antibody responses to childhood immunizations as a clinically relevant parameter that reflects major immune system functions [24].”
“The present report presents the first benchmark dose results for human PFC exposure.”
“PFOA concentrations in drinking water are known to correlate with the serum concentrations of long-term residents in Ohio and West Virginia at an approximate ratio of about 1:100 [12,15,36]. Thus, from these data, a serum-based RfD of 0.1 ng/mL can be translated to a water concentration of 1 ng/L, or 0.001 microgram/L (assuming that no other sources contributed to the PFOA exposure). The current EPA limit for this PFC is 300-fold higher. Thus, the recent evidence on PFC immunotoxicity in humans and toxicity in animal models suggests that current limits for drinking water contamination are too permissive and must be decreased substantially.”
What’s this mean? That lots of kids (and adults) are drinking unhealthy water! This may continue for a long time as new scientific information can take years to manifest in new regulations, and even then, enforcement may take years longer.
Contamination from PFCs is widespread in Minnesota, Ohio, West Virginia, New Jersey, and likely elsewhere. Most of it originated with 3M and DuPont, and the political clout of these has delayed corrective measures. 3M stopped making and using PFOs years ago, but DuPont continues to make, use, and discharge them into what DuPont considers to be it’s rivers.
Litigation against 3M hasn’t gone very far in Minnesota, but it has in West Virginia/Ohio, and DuPont has been forced to fund studies that have revealed more and more health problems. See the website of the DuPont Science Panel.
The Attorney General of Minnesota is pursuing a “natural resources damage” lawsuit against 3M. I don’t know the status of it, but this recent publication ought to ramp it up.
How much time and how much money will it take to get this crap out of our drinking water? How committed are we to getting it done? Are we really even started?
If you drink from a well in an area of known or suspected contamination, get your water tested. If you drink from a public water supply, ask for the test reports. Look at the actual numbers.
For some good reporting and blogging on this recent development in the ongoing PFO scandal see:
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